Mistake - Clear cooked at 300 degrees for 25 minutes.

[KLR]

I tried my first attempt at powder coating this weekend. I used Smoke's Clear and a cool whip container. I set them on end on non-stick foil. Everything looked to be going fine until I used my IR thermometer to check them at the end of the cycle. It was 300 degrees. I let it cook another 5 minutes, but 300 was the max my toaster oven could do.

Yep, stupid mistake. I should have tested the oven before I started.

So what I have are clear coated bullets cooked for 25 minutes at 300 degrees.

They look pretty good. I smashed one with a hammer and the coating didn't flake, I resized a couple and they look fine. If I really work at it, I can scrape it off the nose with difficulty, but it doesn't come off in flakes.

So what should I do now? Can I reheat to 400 in a good oven? Throw them in the pot and recast them? Remove the coating with ??? and recoat? Shoot a few and check for leading?

Here's a pic. The .358 bullets have been sized.

[Jlw6636]

Load them and check for leading. There are several threads and YouTube videos of people PC at tempatures in the 200’s to keep from lossing BHN from water quenching .

[jcren]

Ir thermometers are not very accurate on shiny surfaces or as oven thermometers. Pick up a couple basic dial type oven thermometers wherever has baking supplies near you and lay them in the tray as a trial to see how your oven is working. Bullets look good, and if the coating didn't flake on the smash, I would shoot em. Btw, my oven tops out at 375 or so, so I just cook em a few more minutes and go with it.

[Chainsaw.]

Run em. Elvis ammo, on you tube, did alot of experimentation with eastwoods powder, he found he could bake at temps as low as 275 and still get good results. He did it in the persuit of trying to find a way to cook buckets of bullets all jumbled together with out them glue them selves to one another.

[KLR]

Thanks, guys. I'll give them a try.

[Conditor22]

WAtch for leading in the barrel. I'd load and shoot all of them soon IF PC is not fully cured it may react to the smokeless powder in the case

[Dragonheart]

And who could possibly know more about polymer physics than YouTube Elvis?

I personally have been powder coating since 2012 and just completed PC 10K bullets last week, so I have done a few coatings over the years and I have never experienced barrel leading. I think the reason for my success was learning the PC process from professionals in the business, chemists and polymer physicists.

I asked the question years ago, "Is there wiggle room in the curing process?" I was told Yes, but that can vary due to the type of polymer and the additives, so it is always best to follow the manufacture's curing schedule for the powder used. Call me old school, anal or whatever, but I if I am ignorant on a subject I try to find those with the best minds, education and experience for an answer.

Based on what I have learned and if it were me, I would follow the powder manufacture's instruction's and re-cure the bullets for the specified time and temperature. Yes, you could shoot them, but what do you do if you have leading or PC deposits in the barrel? Is the cleanup time, effort and expense worth it?

An oven that won't get to 400 degrees is worthless for PC. I have new B&D oven I picked up for $7 with the same problem. The only solution is install a PID which cost more than the oven is worth. I have had good success with the Hamilton Beach Countertop Convection ovens, my original is still going since 2012. I also recommend purchasing an accurate glass thermometer to monitor your oven like the Taylor Oven Guide, about $12. Spring thermometers are slow to read and have a high failure rate, been there done that.

[FLINTNFIRE]

Hey thanks for the tip on thermometer , I found with a ir thermometer that readings varied greatly depending on settings on the one i bought and what it was pointing at , glass door on oven different then inside etc , still handy to have around but the taylor oven guide looks sweet , thanks .

[Dragonheart]

Glad to be of assistance.

The IR thermometers are okay for some things like a quick check on mold temperature without removing it from the hot plate oven. They even do a fair job checking the temp of a pan of bullets if you are doing a per-heat. But I have found the IR lacking for anything where you need precision and continually opening the oven is not what you want to do.

[popper]

Shoot a few, if leading, cook the rest at proper temp.

[RKJ]

I don't know what temp my oven gets, but I run it at 325 for 20 minutes and they come out just fine. No leading, no flaking and accurate.

[Traffer]

They are fine shoot them.

[OS OK]

If it were me?
I'd pay attention to what Dragonheart says, he mentions a 'convection oven' & 'glass thermometer' & following manufacturers directions for curing time...or you can chance it and go off 'halfbaked' like these others suggests.
Ever try to clean PC from a barrel? You may get a chance to.



Simply following directions makes for a fine coating and a great day at the range.

[Dragonheart]

You can lead a horse to water, but..............

[fredj338]

Maybe, shooting will tell. When you do your smash test, flatten the bullet, that is when things will flake off. I am the 400deg @ 14-15m in a preheated oven guy. They always work. I also started water dropping the tray out of the oven. it adds a tiny bit of BHN to the finished bullet.

[RKJ]

I know the way I do it works for me. This isn't rocket science.

[KLR]

Thanks for all the advice, guys. I decided to recook them. Tonight I used a different oven and two oven thermometers. I tested the oven before I started.

So, I preheated the oven to 400, put the bullets in, and then cooked them for 15 minutes after the oven got back up to 400. I let them cool by opening the door.

I kept one of the 300 degree bullets to compare. The 400 degree bullets were smoother, slicker, and looked to conform tighter to the bullets. The coating was tougher and way harder to scrap off the nose than the 300 degree bullet. The 300 degree bullets may have been fine and worked okay, but this coating is clearly tougher and sticks better cooked at 400 degrees.

[Dragonheart]

Glad it worked out for you and you were able to actually see the difference.

My only comment is when you look at the thermometer realize it is measuring the temperature of the air in the oven and not the surface temperature of the bullets. Curing time & temperature is based on the temperature of the substraight of the object coated, not the air temperature. On a small batch like you did I am sure it wasn't a problem.

When I cook several thousand bullets two 220V elements can bring the oven temperature to 400 degrees fairly fast, but it can take a half an hour or more longer to bring the temperature of the bullets substraight up to 400 degrees. At that point I give it 15 minutes, as a little extra time will do no harm.

[KLR]

At that point I give it 15 minutes, as a little extra time will do no harm.

Thanks. That's good to know. My total time in the preheated oven was 32 minutes. I waited until the temp stabilized before I started my 15 minute count down.

[OS OK]

You can lead a horse to water, but..............

................you will still get an argument! hehehehe